/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb.commons.path.fa.match;

import org.apache.iotdb.commons.path.fa.IFAState;
import org.apache.iotdb.commons.path.fa.IFATransition;
import org.apache.iotdb.commons.path.fa.IPatternFA;

import java.util.Iterator;

/**
 * This class is used for cases need traceback.
 */
public class StateMultiMatchInfo implements IStateMatchInfo {

    private final IPatternFA patternFA;

    private final MatchedStateSet matchedStateSet;

    private int sourceStateIndex;

    private Iterator<IFATransition> sourceTransitionIterator;

    private boolean hasFinalState = false;

    public StateMultiMatchInfo(IPatternFA patternFA) {
        this.patternFA = patternFA;
        matchedStateSet = new MatchedStateSet(patternFA.getStateSize());
    }

    public StateMultiMatchInfo(
            IPatternFA patternFA,
            IFAState matchedState,
            Iterator<IFATransition> sourceTransitionIterator) {
        this.patternFA = patternFA;
        matchedStateSet = new MatchedStateSet(patternFA.getStateSize());
        matchedStateSet.add(matchedState);
        sourceStateIndex = 0;
        this.sourceTransitionIterator = sourceTransitionIterator;
        this.hasFinalState = matchedState.isFinal();
    }

    @Override
    public boolean hasFinalState() {
        return hasFinalState;
    }

    @Override
    public boolean hasOnlyPreciseMatchTransition() {
        return false;
    }

    @Override
    public boolean hasNoPreciseMatchTransition() {
        return false;
    }

    @Override
    public boolean isSingleFuzzyMatchTransition() {
        return false;
    }

    @Override
    public IFAState getOneMatchedState() {
        throw new UnsupportedOperationException();
    }

    @Override
    public void addMatchedState(IFAState state) {
        matchedStateSet.add(state);
        if (state.isFinal()) {
            hasFinalState = true;
        }
    }

    @Override
    public IFAState getMatchedState(int stateOrdinal) {
        return patternFA.getState(matchedStateSet.getStateIndex(stateOrdinal));
    }

    @Override
    public int getMatchedStateSize() {
        return matchedStateSet.size();
    }

    @Override
    public int getSourceStateOrdinal() {
        return sourceStateIndex;
    }

    @Override
    public void setSourceStateOrdinal(int sourceStateOrdinal) {
        this.sourceStateIndex = sourceStateOrdinal;
    }

    @Override
    public Iterator<IFATransition> getSourceTransitionIterator() {
        return sourceTransitionIterator;
    }

    @Override
    public void setSourceTransitionIterator(Iterator<IFATransition> sourceTransitionIterator) {
        this.sourceTransitionIterator = sourceTransitionIterator;
    }
}
